Robert Downey, Jr. is mourning the loss of his mother, Elsie Ann Downey, who passed away on Monday at the age of 80 after battling numerous health issues, according to the New York Daily News.

The "Iron Man" actor took to Facebook on Friday to share the news of his mother's passing, along with posting a touching tribute to the woman whom he owes everything to.

"As promotion for 'The Judge' kicks off this weekend, I feel the need to run the risk of over sharing," he began the post. "My mom passed away early this week. I wanna say something about her life, and a generic 'obit' won't suffice."

In the heartfelt post, the actor wrote that his mother was born outside Pittsburgh in 1934. In the mid-1950s she dropped out of college and moved to New York with dreams of "becoming a comedienne." In 1962, she met actor and filmmaker Robert Downey, Sr. The couple later married and had two children - Robert Jr. and his sister Allyson.

The two collaborated on several projects, including "Two Tons of Turquoise to Taos Tonight" where Elsie played 17 different characters. However, Elsie's personal life and acting career began to suffer due to alcohol addiction.

"By the mid '70s, the downside of drug culture caught up with many artists," he wrote. "She was an alcoholic. As the marriage suffered, she continued to work, but not for long. I remember living with her and her boyfriend Jonas, (who became a second father to me) in a 2 room 5 story walk up in Manhattan after that...Bunsen burner for a stove, cockroaches, broken dreams."

By 1990, Elsie decided to seek treatment, "just in time to enjoy several decades of heart disease, bypasses," the actor wrote. He added that he suffered the same addiction when starting his own career.

"In the summer of 2004, I was in bad shape," he added. "She called me out of the blue, and I admitted everything. I don't remember what she said, but I haven't drank or used since. Eventually, when finances allowed, we were able to move her out to LA. She had a special affinity for my firstborn son Indio."

In the post, he revealed that his mother was diagnosed with "Medical Incredible," but added that he shared "many fond memories" with his mother and family. In March, Elsie suffered cardiac arrest and was put on life support and her condition eventually worsened.

Downey wrote: "She was my role model as an actor, and as a woman who got sober and stayed that way. She was also reclusive, self-deprecating, a stoic Scotch-German rural Pennsylvanian, a ball buster, stubborn and happy to hold a grudge. My ambition, tenacity, loyalty, 'moods,' grandiosity, occasional passive aggression, and my faith...That's all her...and I wouldn't have it any other way."

"If anyone out there has a mother, and she's not perfect, please call her and say you love her anyway..."

He concluded his eulogy with a photo of his mother as a young woman with the caption: "Elsie Ann Downey. 1934-2014."